Electric iron



' June 18, 1935. F; w. SCHARF ELECTRIC IRON Filed Nov. 27, 1931 2 Sheets-Sheet -1 Patented June 18,; 1935 2,004,962

UNITED STATES PATENT OFFICE ELECTRIC moN Frank W. Scharf, Chicago, Ill., assignor, by mcsne assignments, to McGraw Electric Company, Chicago, 111., a corporation of Delaware Application November 27, 1931 Serial 517,499

10 Claims. (01. 219-25) An object of this invention is to provide a is closed when the two are in contact, as shown thermostatic electric iron in which the thermoin Fi static element is almost entirely protected from These membe a p c d from each other, direct radiations from the heating element and and are carried upo Suitable insuletin! Stripe ,5 from the filler block. 2| which serve also to insulate them from each 5 This and other objects, as will hereinafter her, eac o t e embe being c ct d appear, are accomplished by' this invention to suitable electrical terminal pins 22 carried by which is fully described in the following speciut insulat d fr m th lock 2 in a mann r fication and shown in the accompanying dr common to this'art. This thermostatic switch ings, in whichassembly is secured in place by means "of screws 10 Figure l'is a longitudinal section on the line a tu a a nut filler block ll I-l of Fig. 2 showing an iron embodyin th is provided with an open space H'- overlying.

invention; the recess I5 and groove l6. Into this space Fig. 2 is a. transverse section on the line extends a metal cover 26 which has a ground 22 of Fig. 1;, or otherwise finished face overlying and making Fig. 3 is a partial plan view slightly reduced Contact with the finished face of the fin l6,

of the center of the sole plate of Figs. 1. and the cove! and fin p y'b 0f ubstlm- 2 showing the recess, th fin, and a groove tially the same thickness. The cover is secured surrounding the same; in place by means of a screw 21 and a nut 2 F 4 is a partial section similar to the lower on the S 1 left-hand portion of Fig. 1' showing a modified A sheet metal cover 19 surrounds the filler form of the invention; oc but is spaced therefrom, and this to- Fig. 5 is a, vie ila t Fig 1 showing. gether with a handle 30 are secured in place still another modification; by means of screws 3| which are threaded into 26 Fig'. 6 is a transverse section on the line 6- 6 filler bleekn adjusti c e 3 l8 of Fig. 5; and v a threaded into the-filler block and has an insulat- 7'1 plan View f the sole plate of ing end 33 adjustably bearing upon the fixed '5 with the thermostatic switch in place. member 0f the Switch, this Screw d nB The embodiment h n in Figs 1, 2 and 3 through the lower part of the handle, and hav- I comp ses an electric iron having a. sole plate m a Winged knob j y u d he eg I0 and electric heating element II, and a weight on by m a of a Screw This adjusting knob member or filler block l2 secured together by has Pointer 35 which is adapted to swing means of screws l3, H. The sole plate In is a radiated scale on a plate 31, which is held in provided with a centrally located recess 15 Place by the Screws This plate carries suit-v which is surrounded on two sides, and preferably able S p which prevent the screw 32 from u the front end,-with a groove "5 which need making more than a half turn. t b quite so deep s t recess itsemv The Thus it will be seen that the thermostatic groove thus prQvides n upwardly extending fin switch may-be caused to open and close for prewhich n this form is p eferably of the same determined temperatures of the bi-metal strip 40 height-as the top of the sole plate, so that the d that the Points at which the switch 40 two may be ground oil, or otherwise finished to W111 open and, Close may be changed b means the same height, Th purpose o this fin w of the adjusting screw 32. It is highly desirable later be explained. that the temperature of the bi-metal strip 2| -This recess is provided with a. slightly raised Should be dependent almost whol upon the strip [1 on which i secured a thermostatic temperature of the sole plate immediately beswitch I8 which has a relatively fixed switch neath and that it Should be affected as lime 'member l9, and a movable member 20, the Possible by the temperature of heating l tt being a h t Strip composed, element ll and of the filler block II. For this similar mQtaIS'ha g difie t cmemcientsof reason the metal cover 26 is placed over the i expansion c thai; thi member tends to bend thermostatic switch so as to intercept radiations 50 I and assume difierentpositions,- depending. upon from the members H and I and by fl ng its temperature. It is tipped with ins lati n these radiations transmit the heat through the. 2|] so as to prevent its making electrical contact fin to the sole plate. with the sole plate. Boththe members l9 and At the same time the groove l6 serves an- 20 carry current and act as a switch which other purpose, namely, of preventing heat from. i

I the top of the sole plate directly afiecting the bi-metal strip. This groove causes theheat to travel down through the sole plate, thereby affecting the face of the sole plate and raising its temperature before enough heat is radiated to the bi-metal strip to cause it to move away from the fixed member l9.

In Fig. 4 is shown a modified form of the invention in which is a sole plate Ill and electric heating element II and weight member l2. A thermostatic switch Iv is mounted as before, but is covered by means of a fin I6 which is integral with the sole plate, but which is cored out to provide a chamber 38. The op-.

eration of the device, as shown in Fig. 4, is the same as that previously described, but the fin and cover by being integral will more efilciently transmit the heat to the sole plate, therebymaking doubly sure that the thermostatic switch will be aifected mainly by the temperature of particularly the electric heating temperature of the parts above the sole plate.

In Figs. 5, 6 and 7 is shown still another modification of the invention in which there is a sole plate W, a heating element It, a weight -member or filler block I2 these being secured together by means of screws 13" and II". The soleplate is made deeper and is provided with a peripheral ledge 1, the center of the sole plate having a recess IS in which is located the thermostatic switch I8 the one here shown being of the slow-break variety. This recess is surrounded by a groove l5, as in the other two forms, this groove preferably extending along both sides and the front end, as shown, thereby forming a deep fin 38. The recess li is made as narrow as may be providing as little clearance as possible on the sides for the switch l8. This reduces the cold spot in the center of the iron to a very considerable degree, and protects the switch elements from direct radiation of the parts above, as will presently be explained. I

The weight member l2 is made U-shaped and is cut back at an angle so that the limits of its radiation are indicated by'the lines XX of Fig. 6. It will be noted that these lines are so chosen that they pass over the top of the thermostatic switch so that there will be no direct radiations, from the sides at least, fromthe filler block 12 or from the heating element ll" directly to the,therm.ostatic switch. The handle 30 is secured to the iron by means of screws 39 which are threaded into cross members 40, which are secured to the filler block |2, as shown in Fig. 6. Thus it will be seen that a number of modifications are provided of this automatic electric iron in which the thermostatic element is protected against direct radiations of the-heated parts which lie above it, element and the filler block.

while I have shown and described but a few embodiments of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made which do not depart from the spirit and scope of the invention as disclosed in the appended claims.

I claim:

1. In an electric iron or the like, a sole plate, a heating element, a weight member, a. thermostatically-operated switch in series circuit with' the heating element, said sole plate having a a chamber therein with walls integral with the sole plate and extending above the sole plate for substantially enclosing said switch so as to prevent direct radiation thereto from the weight member or heating element.

2. In an electric iron or the like, a soleplate, a heating element, a weight member, a thermostatically-operated switch in series circuit with the heating element, said sole plate having a recess therein for substantially enclosing said switch so as to prevent direct radiation thereto from the weight member or heating element, and a groove along each side of the recess forming a fin for carrying heat to the sole plate.

3. In an electric iron or the like, a sole plate,

' a heating element, a weight member, a thermostatically-operated switch in series circuit with the heating element, said sole plate having a chamber therein with walls integral with the sole plate for-substantially enclosing said switch so as to prevent direct radiation thereto from the weight member or heating element, and a groove along each side of the chamber forming a fin for carrying heat to the sole plate.

4. In an electric iron or the like, a sole plate, a heating element, a weight member, a thermostatically-operated switch in series circuit with the heating element, said sole plate having an opening therein with side walls integral with the sole plate and a metal cover secured thereover for substantially enclosing said switch so as to prevent direct radiation thereto from the weight member or heating element, and a groove along each side of the chamber forming a fin for carrying heat to the sole plate.

5. In an electric iron or the like, a sole plate, a heating element, a weight member, a thermostatically-operated switch in series circuit with the heating element, said sole plate having a recess therein adapted to receive the switch, a groove along each side of the recess forming a fin, and a metal cover secured thereover to'receiveradiant heat from the heating element and weight member, the edges of the cover bearing upon the fin to transmit this heat thereto.

6. In an electric iron on the like, a sole plate, a heating element, a weight member, a thermostatically-operated switch in series circuit with the heating element, said sole plate having a recess therein adapted to receive the switch, a groove along each side of the recess forming a fin ,of the same height as the sole plate, and a metal cover secured thereover to receive radiant heat from the heating element and weight memher, the edges of the cover bearing upon the fin to transmit this heat thereto.

7. In an electric iron or the like, a sole plate,

a heating element, a weight member, a thermo-v 8. In an electric iron or the like, a sole plate,

a heating element, a weight member, a thermostatically-operated switch in series circuit with the heatingelement, said sole plate having a recess therein for substantially enclosing said switch so as to prevent direct radiation thereto from the weight member or heating element, and a groove along each side of the recess, said weight member being cutback so as to have no part alongside the recess capable of sending 10. Inaneleetricironorthelike.aaoleplate, heat radiations direct to said thermostatic a heating element for heating the sole plate, switch. said sole plate having a slot and a groove adja- 9. In an electric iron or the like, a sole plate, cent the slot forming a fin of substantially the 5 aheatingelementforheatingthesoleplate,said sameheightasthetopoi'thesoleplateior in- 5 sole plate having a slot and a groove adjacent tempting heat rays and for transferring this the slot forming a fin for intercepting heat rays heat to the lower portion 01' the sole plate, and and for transferring this heat to the, lower pora thermostat for controlling the heating element tion of the sole plate, and a thermostat for conlocated in the slot.

l0 trolling the heating element located in the slot. FRANK W. BCHARF. 1o 

